Backlight module

Abstract

A backlight module includes a light source, a light guide plate and at least one optical film. The light source has a plurality of light emitting devices. The light guide plate includes a light entrance portion, a main body portion and at least one positioning structure. The light entrance portion has a top surface and a light entrance surface. The light source is disposed corresponding to the light entrance surface. The top surface is adjacently connected to the light entrance surface. The main body is connected to the light entrance portion and has a first light extraction surface connecting the top surface. The positioning structure is disposed on the top surface and corresponding to an interval between two adjacent light emitting devices, and has an accommodating space. The optical film is disposed above the light guide plate and has at least one protruding portion disposed in the accommodating space.

What is claimed is: 
     
       1. A backlight module, comprising:
 a light source having a plurality of light emitting devices; 
 a light guide plate comprising:
 a light entrance portion having a top surface and a light entrance surface, wherein the light source is disposed corresponding to the light entrance surface, and the top surface is adjacently connected to the light entrance surface; 
 a main body portion connected to the light entrance portion and having a first light extraction surface, the first light extraction surface being connected to the top surface; and 
 at least one positioning structure disposed on the top surface of the light entrance portion, the positioning structure being disposed corresponding to an interval between two adjacent ones of the light emitting devices, the positioning structure having an accommodating space; and 
 
 at least one optical film disposed above the light guide plate, the optical film having at least one protruding portion, the protruding portion being disposed in the accommodating space. 
 
     
     
       2. The backlight module according to  claim 1 , wherein the positioning structure further has a first surface, a second surface and a third surface, the second surface and the third surface respectively extend from two sides of the first surface and along the direction toward the main body portion, and the first surface, the second surface and the third surface define the accommodating space. 
     
     
       3. The backlight module according to  claim 2 , wherein the positioning structure further has a fourth surface connected to the first surface, the second surface and the third surface, and the fourth surface overlaps the protruding portion of the optical film. 
     
     
       4. The backlight module according to  claim 2 , wherein the first surface, the second surface and the third surface are in a U-shaped arrangement. 
     
     
       5. The backlight module according to  claim 1 , wherein the optical film further has a base plate, the base plate has a second light extraction surface and a side surface connecting to the second light extraction surface, and the protruding portion of the optical films is located at the side surface. 
     
     
       6. The backlight module according to  claim 1 , wherein the numbers of the at least one optical film and the at least one positioning structure are respectively plural, and the accommodating space of each one of the positioning structures only accommodates the protruding portion of one of the optical films. 
     
     
       7. The backlight module according to  claim 1 , wherein the numbers of the at least one protruding portion of the optical film and the at least one positioning structure are respectively plural, and the protruding portions of the optical film are respectively disposed in the accommodating spaces of the positioning structures. 
     
     
       8. The backlight module according to  claim 1 , wherein the light guide plate further includes a plurality of protruding structures disposed on the light entrance surface of the light entrance portion, and each one of the light emitting devices is located between two adjacent ones of the protruding structures. 
     
     
       9. The backlight module according to  claim 1 , wherein the light entrance portion further includes a bottom surface opposite to the top surface, and the distance between the top surface and the bottom surface gradually decreases along a direction away from the light entrance surface. 
     
     
       10. The backlight module according to  claim 1 , wherein the positioning structure protrudes from the top surface of the light entrance portion, and the width of the positioning structure gradually decreases along the direction away from the light entrance surface.